In a landmark decision, Mr Justice Eady refused to grant an order to protect the anonymity of a police officer who is the author of a blog called NightJack.

The officer, Richard Horton, 45, a detective constable with Lancashire Constabulary, had sought an injunction to stop The Times from revealing his name.

In April Mr Horton was awarded the Orwell Prize for political writing, but the judges were not aware that he was revealing confidential details about cases, some involving sex offences against children, that could be traced back to genuine prosecutions.

His blog, which gave a behind-the-scenes insight into frontline policing, included strong views on social and political issues, including matters of “public controversy,” the judge said.

The officer also criticised and ridiculed “a number of senior politicians” and advised members of the public under police investigation to “complain about every officer . . . show no respect to the legal system or anybody working in it.”

Mr Horton has now deleted his website and received a written warning from his force.

He has received several offers to publish a book after using the success of the blog to attract a literary agent.

Some of the blog’s best-read sections, which on occasion attracted nearly half a million readers a week, were anecdotes about the cases on which Mr Horton had worked.

The people and places were anonymised and some details changed but they could be traced back to the prosecutions.

In the first case dealing with the privacy of internet bloggers, the judge ruled that Mr Horton had no “reasonable expectation” to anonymity because “blogging is essentially a public rather than a private activity”.

Coming down in favour of freedom of expression, the judge also said that even if the blogger could have claimed he had a right to anonymity, the judge would have ruled against him on public interest grounds.
The police officer, the judge said, had argued that he should not be exposed because it could put him at risk of disciplinary action for breaching regulations with his disclosures.

But Mr Justice Eady criticised that argument as “unattractive to say the least”.

He added: “I do not accept that it is part of the court’s function to protect police officers who are, or think they may be, acting in breach of police discipline regulations from coming to the attention of their superiors.”

The judge added that there was “much force in the argument that any wrongdoing by a public servant, save perhaps in trivial circumstances, is a matter which can legitimately be drawn to the attention of the public by journalists. There is a growing trend towards openness and transparency in such matters.”

He added: “It would seem to be quite legitimate for the public to be told who it was who was choosing to make, in some instances, quite serious criticisms of police activities and, if it be the case, that frequent infringements of police discipline regulations were taking place.”

The action arose after a Times journalist, Patrick Foster, worked out the identity of the NightJack blogger “by a process of deduction and detective work, mainly using information on the internet,” the judge said.

Hugh Tomlinson, QC, for the blogger, had argued that “thousands of regular bloggers who communicate nowadays via the internet under a cloak of anonymity would be horrified to think that the law would do nothing to protect their anonymity of someone carried out the necessary detective work and sought to unmask them”.

The judge said: “That may be true. I suspect that some would be very concerned and others less so.”

But “be that as it may”, he added, the blogger needed to show that he had a legally enforceable right to maintain anonymity in the absence of a genuine breach of confidence, by suppressing the fruits of detective work such as that carried out by Mr Foster.

Mr Tomlinson had argued that the blogger wished to remain anonymous and had taken steps to preserve his anonymity.

He said that The Times was aware of his wish; and that there was no justification for “unmasking” him, as he was entitled to keep his identity as the author of the blog private and confidential.

But Mr Justice Eady said that the mere fact that the blogger wanted to remain anonymous did not mean that he had a “reasonable expectation” of doing so; or that The Times was under an enforceable obligation to him to maintain that anonymity.

Antony White, QC, for The Times, argued that there was a public interest in non-compliance by a police officer with his obligations under the statutory code governing police behaviour; and also with general public law duty on police officers not to reveal information obtained in the course of a police investigation, other than for performing his public duties.

When first confronted by The Times, Mr Horton refused to confirm or deny that he was the blog’s author.

Lancashire Constabulary began an investigation after being told of his identity and issued him with a written warning.

A police spokesman said: “The commentary in the blog is indeed the work of a serving Lancashire detective and clearly the views and opinions expressed are those of the author himself and not those of the wider constabulary.

“We have conducted a full internal investigation and the officer accepts that parts of his public commentary have fallen short of the standards of professional behaviour we expect of our police officers.

“He has been spoken to regarding his professional behaviour and, in line with disciplinary procedures, has been issued with a written warning.”